Big-bore revolver rounds not chambering easily

[DrCaveman]

Before i ever had even heard of castboolits.com, i read the lyman 49th manual and the 4th edition cast handbook. One area i paid particular attention to in each book was pressure signs upon shot brass, and brass inspection prior to reloading.

I was mostly loading high-pressure 30-06 rounds at the time, and had just gotten into some 357 mag and 45 auto loading. Jacketed and plated were the projectiles of choice then, until i saw the price difference benefit of buying cast lead, and then of course learned that i could make them at home and now i am a cast boolit addict.

During this development i have seen flattened and cratered primers. Ive culled quite a few split necks. Ive culled brass beat to heck by autoloaders. Ive trimmed brass that had stretched substantially.

What ive yet to experience is the "ringing" shown on page 48 of lyman 49th.

Now to the story

Shooting last weekend my tried-and-true 460 magnum load was performing well. I did however notice some soot buildup in my chambers that i hadnt seen before. Then some rounds became difficult to fully chamber (no 454 or 45 colt loads has been fired since last cleaning) and so i cherry picked the rounds that loaded easily. I saved the bad chambering rounds and kept a few of the good rounds for further inspection

Caliper mesurement showed at most .002" difference of diameter from mouth to rim, between the two loaded rounds. It was hard to gauge every single point, but i am pretty confident about this measurement.

Bad rounds ALL possessed a visible ring about 3/4" from the rim. I wasnt even remotely paying attention for this while reloading, so i am not surprised i missed it.

My question is: am i looking at worn brass here, destined for case failure (hence i will pull it and trash the brass!), and why would this prevent me from fully chambering the cartridge? Angels looking upon me?

Never seen or experienced case separation and would prefer to keep it that way...

Any more information i can provide to help answer this, no problem

Thanks, and good shootin to ya

[CastingFool]

I think pictures of the "bad" rounds would help. I'm sure other more experienced members here would have something to add.

[osteodoc08]

What boolit are you shooting? What are they sized to? What brass? What OAL? Does the ring/bulge follow the shape of the boolit? How much crimp are you using?

Problems I've run into is using a boolit that is too far oversized once stuffed in a case prevents it from chambering. I've also crimped too aggressively and put a wave in the brass. It typically occurs just past the heel of the bullet. If throats are undersized and using a Keith style boolit, I've had the front driving band not play nice and had to seat the boolit a tad deeper. I've also not flared the casing enough and crinkled brass or even shaved a piece of lead that gets caught at the mouth of the case mess up the works. I've also had this happen for unknown reasons. I pull components, resize the casing, reload with fresh and try again. You've already cleaned the chambers.

My M57 chambers and throats are generous from the factory. I can usually plop my blackhawk "rejects" into it and fire away without issue.

Perhaps someone with more experience than me can chime in.

[44man]

Revolver brass does not stretch like rifle brass, never seen head separation.
According to marks on my cartridge box, one batch of .44 brass has been fired with full power loads 43 times and I just lost one to a small crack at the crimp.
What is your size die doing? What brand of dies?
All straight wall brass has a slight taper and .002" is about right.
Carbon and lube on the outside of brass is common with cast.

[Silver Jack Hammer]

A bulge on a .45 Colt cartridge at the location indicated on page 48 of Lyman 49th has been observed in my shooting associates. Without further information on your equipment, I've attributed this to carbide dies and not fully inserting the tapered cartridge case into the die. One reason this happens is a shellplate that is too thick such as the Dillon which prevents us from fully inserting the cartridge in the die. Another issued is the handloader who backs the die out too far to protect the carbide ring when reloading.

Some firearms manufacturers make a slight taper in the chamber dimensions, which is correct to SAMMI specs for the .45. Then we use carbide dies which resize at the die mouth, we end up with brass which is not resized to the proper tapered dimensions. Then if the case isn't inserted into the die all the way we get that bulge.

Just yesterday I ordered a steel resizer die and am going back to resizing with lube. Hornady makes a die with two carbide rings, one on the base of the die and another one to resize the case mouth with the smaller dimension. This die is over $100.00. I spent $20.00 on the steel die.

I've had a case separate in the chamber at the location shown on Lyman's 49th on page 48, there was no safety issue. The brass doesn't contain any pressure. I just used a pick to remove the remaining portion of the case stuck in the chamber and threw away the rest of that lot of brass.

[snowwolfe]

Been reloading for the big bores since the early 70's and some far in every case of oversized cases its been traced to crimping and or sizing problems. Maybe not true in your case but I would explore this area first.

[DrCaveman]

95180

here are the rounds. bad ones on top, easy loaders on the bottom. Ring was pretty evident when I took the pic, hopefully it shows up in the attachment.

Interesting to note too that I loaded 15 rounds of a favorite using the lee 405 gr boolit. Also loaded 5 using the lee 300 gr GC boolit. Of the 405 gr loads, only 2 wouldnt chamber. Of the 300 gr boolit, 3 of the 5 wouldnt chamber. Hmmm...

both bollits were sized to .4525", but the 300 gr drops from the mold a lot smaller. Like, maybe .453" if im lucky. The 405 gr of course drops around .458" since it is made for the 45-70.

I am indeed using carbide dies, of the Lee variety. I guess there is a possibility that I short stroked a few of the resizing operations... but it seems like the decapper is positioned so that I cant really get away with too much variation without noticing.

I do not use any post-sizing die (like lee FCD) for this caliber. Just seat and crimp in one move. Also, I havent begun trimming my 460 cases since it was a waste of time the last few times I tried. nothing to trim! maybe time to rethink that move.

could varying case length, hence varying roll crimp, be causing tough chambering? all the offending cartridges will load until about 3/8" of case is sticking out of cylinder. then it gets real tough and if I dare push any further, then extraction requires a whack with a mallet. without the round being fired.

[44man]

(Some firearms manufacturers make a slight taper in the chamber dimensions, which is correct to SAMMI specs for the .45. Then we use carbide dies which resize at the die mouth, we end up with brass which is not resized to the proper tapered dimensions. Then if the case isn't inserted into the die all the way we get that bulge.

Just yesterday I ordered a steel resizer die and am going back to resizing with lube. Hornady makes a die with two carbide rings, one on the base of the die and another one to resize the case mouth with the smaller dimension. This die is over $100.00. I spent $20.00 on the steel die.) Quote;
Exactly, you can't size tapered brass with anything but a steel die that is also tapered.
I do get by with the Hornady TN dies and understand the problems but I love the expanders, seaters and crimp best. The Hornady dies for the .500 S&W that I use for the JRH are steel that needs lube and are perfect.
Most all it takes is die adjustment anyway.
I am going out on a limb but some die makers do not understand what they make. Why not a full length carbide die that is tapered to fit the brass? It is because most have a small ring fit to necks and not the rest of the brass without additional cost.
TN is a coating, not carbide cast, diamond cut or whatever so there is no reason the whole inside can't be coated.

[bhn22]

A full length tapered sizing die would be phenomenally expensive to manufacture, the rejection rate would be really high. The two diameter system used by Redding makes a lot of sense in comparison. You might be able to approximate tapered dies if you first size cases with a Lee FCD with the guts removed, then used a standard carbise sizing die to size the case down to the length of the seated bullet. It would be a pain, but in the long run could be worth it.

[NVScouter]

Shoot lots of 45LC in that 460? I bet you have fouling at the throat. Happens in lots of duel ammo pistols, also a long nosed boolit like yours needs a good throat.

I shoot the LEE340g .458 sized to .454 in my 45LC and if I dont trim my brass or I get wax build up in my seating die they can be off.

[44man]

A full length tapered sizing die would be phenomenally expensive to manufacture, the rejection rate would be really high. The two diameter system used by Redding makes a lot of sense in comparison. You might be able to approximate tapered dies if you first size cases with a Lee FCD with the guts removed, then used a standard carbise sizing die to size the case down to the length of the seated bullet. It would be a pain, but in the long run could be worth it.
Not with titanium nitride, it is a coating and cheap.

[454PB]

95180



I do not use any post-sizing die (like lee FCD) for this caliber. Just seat and crimp in one move. Also, I havent begun trimming my 460 cases since it was a waste of time the last few times I tried. nothing to trim! maybe time to rethink that move.

could varying case length, hence varying roll crimp, be causing tough chambering? all the offending cartridges will load until about 3/8" of case is sticking out of cylinder. then it gets real tough and if I dare push any further, then extraction requires a whack with a mallet. without the round being fired.

I always seat and crimp in two separate operations just to avoid this kind of problem. If all the cases aren't exactly the same length (and few of us trim handgun cases), you can deform the case as the crimp is applied. By crimping in a second operation, you can actually feel the amount of force applied and STOP before the case is buckled.

[Treeman]

Case head separations are rare in straightwalled cases but not unknown. The rings on your cases do have the look of an incipient case separation........but in every case that I have had such marks on my brass it has been due to chamber rattle where there was a contact point in the chambers or storage rattle where rounds contacted something at that point and had a chance to be vibrated in transport. Break one or two down and do a scraping probe test on the interior to see if there is thinning of the brass. Probably not but you can be SURE.

[john hayslip]

I agree with 454PB's answer. If cases are trimmed to length put a case in shell holder and raise the ram - then screw the die down til it touches (call this the "first position")- it'll then be on the crimping shoulder - and the die is probably NOT screwed all the way down to the shell holder. Back off about 10 degrees. Set the seating depth. Now screw the die down to the first position and enough more to give the crimp you want - as you're screwing down the whole die you do not change the seating depth for the bullet because the bullet is being pushed into the case the same amount as the crimping shoulder is coming to the case's top.
If your cases aren't trimmed to the same length this won't work well.
The same procedure works on rifle cases. If you incorrectly set the die to far past (first position) to start you usually get a bulge under the shoulder on a rifle case.
I know - been there, done that!!! Ken Waters was kind enough to write me a letter explaining the above.

[Bullshop Junior]

Revolver brass does not stretch like rifle brass, never seen head separation.
According to marks on my cartridge box, one batch of .44 brass has been fired with full power loads 43 times and I just lost one to a small crack at the crimp.
What is your size die doing? What brand of dies?
All straight wall brass has a slight taper and .002" is about right.
Carbon and lube on the outside of brass is common with cast.

I had a box of brand new winchester factory (I know I know) 454 Casull ammo that half of them split or seperated first firing.

[Bullshop Junior]

95180



I do not use any post-sizing die (like lee FCD) for this caliber. Just seat and crimp in one move. Also, I havent begun trimming my 460 cases since it was a waste of time the last few times I tried. nothing to trim! maybe time to rethink that move.



That may be part of your problem right there. I never crimp and seat in the same step. I may thread the seating die down just enough to close the flare, but not enough to crimp. It usually puts a bulge in the cartridge right under the crimp somewhere.

[Whiterabbit]

Wish I had some input. I've tried a BUNCH of oddball stuff, and have experienced "difficult to chamber" many times. None of which apply to your observations here.

My only guess is that the "something" (aka root cause) is causing the chambers to soot up, is actually causing what was marginal but no problem to chamber, to fall off the edge and be hard to chamber. In other words, based on your description, I'll bet you ALWAYS "had this problem" and just never saw it because you were on the hairy edge of the cliff for being tough to chamber, but never saw it till you got the fouling in the chamber.

Meaning you could fix whats on the edge, or fix the fouling and I bet the problem goes away.

--------------

Now:

Here's a real suggestion. Pull 5-10 of the rings. Take them to your local university materials department (assuming you live near a university with a materials engineering department), and have a sit down with either the department chair, or the teacher of the Failure Analysis class. Tell them you have a neat student project they can have. Give them the ringed cases, and a few new or 1x cases, explain what's going on. The students can take on that project, cut the brass in half, mount and polish it, inspect the microstructure of the sectioned brass, compare to prime brass, and write a report about it. The professor can forward the powerpoint to you for feedback.

You help a student get his class project material, and in return you get a report on whats going on at the microstructural level.

theoretically, anyways. That is, if you are interested in that kinda stuff.

[Bullshop Junior]

--------------

Now:

Here's a real suggestion. Pull 5-10 of the rings. Take them to your local university materials department (assuming you live near a university with a materials engineering department), and have a sit down with either the department chair, or the teacher of the Failure Analysis class. Tell them you have a neat student project they can have. Give them the ringed cases, and a few new or 1x cases, explain what's going on. The students can take on that project, cut the brass in half, mount and polish it, inspect the microstructure of the sectioned brass, compare to prime brass, and write a report about it. The professor can forward the powerpoint to you for feedback.

You help a student get his class project material, and in return you get a report on whats going on at the microstructural level.

theoretically, anyways. That is, if you are interested in that kinda stuff.

Or he could get thrown in jail nd have the school go into lock down.

[DrCaveman]

Yeah, the university in this town might not take as kindly as the A&M/eng school up the freeway
Meaning that I live in the green & yellow hippy town

Still, white rabbit I like your idea. I might look into that

I also figured the chamber fouling was a big part of the problem, until I got home and cleaned the snot out of those things til empty cases dropped in and fell out under gravity. The cleaned a little more (yeah the 45 colt rounds leave a mess)

The bad rounds pictured above will still not chamber

Maybe I can use my 45-70 factory crimp die. I think it might be too long however

Tonite I will mess around with the seating die more, and see if I can recreate the problem

Thanks for the help everyone

[Whiterabbit]

(yeah the 45 colt rounds leave a mess)

I wont say I told you so but.... wait, yes I will! :kidding:

If the cylinder is clean, then I wonder two things. #1, are the cases getting caught up in exactly the same spot every time as you try to push them in, and #2 are they out of round. crooked bullet, whole case bent, etc. something like that.

[Bullshop Junior]

Yeah, the university in this town might not take as kindly as the A&M/eng school up the freeway
Meaning that I live in the green & yellow hippy town

Still, white rabbit I like your idea. I might look into that

I also figured the chamber fouling was a big part of the problem, until I got home and cleaned the snot out of those things til empty cases dropped in and fell out under gravity. The cleaned a little more (yeah the 45 colt rounds leave a mess)

The bad rounds pictured above will still not chamber

Maybe I can use my 45-70 factory crimp die. I think it might be too long however

Tonite I will mess around with the seating die more, and see if I can recreate the problem

Thanks for the help everyone

Ive used my sizing die without the decaping rod to help het rid of a bulge before.

[Char-Gar]

I am guessing a chip caught in the reamer when one charge hole was reamer and scored a round circle in the charge hole. The brass expands a bit into the chip ring and when sized, this is what you get. You may or may not find one charge hole gives harder extraction than the other. Again, this is a guess.

It is not a bright ring that is a harbinger of incipient case separation. It is either an issue with the sizing die or one charge hole.

There is always the possibility you jugged a charge hole with your handloads. You been playing around with wads or fillers?

[DrCaveman]

Char gar you may be on to something, thanks for chiming in
The percentage of my brass that are displaying this problem is around 1/5th of those which I most recently sized

Bright light and magnifying glass when I get home
Do you think this reaming problem would be visible?

No wads or fillers in 460 magnum for me so far

[bhn22]

Not with titanium nitride, it is a coating and cheap.

I'm betting the extra surface contact area would probably require lubrication anyway.